{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,5]],"date-time":"2026-04-05T10:10:47Z","timestamp":1775383847955,"version":"3.50.1"},"reference-count":44,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2018,6,28]],"date-time":"2018-06-28T00:00:00Z","timestamp":1530144000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100013287","name":"Science Challenge Project","doi-asserted-by":"publisher","award":["TZ2016003-2"],"award-info":[{"award-number":["TZ2016003-2"]}],"id":[{"id":"10.13039\/501100013287","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61734001"],"award-info":[{"award-number":["61734001"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61521004"],"award-info":[{"award-number":["61521004"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2016YFB0400100"],"award-info":[{"award-number":["2016YFB0400100"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2017YFE0100300"],"award-info":[{"award-number":["2017YFE0100300"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100016307","name":"NSAF","doi-asserted-by":"publisher","award":["U1630109"],"award-info":[{"award-number":["U1630109"]}],"id":[{"id":"10.13039\/501100016307","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Sino-German Center for Science Promotion, NSFC and DFG","award":["GZ1309"],"award-info":[{"award-number":["GZ1309"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>It is a fact that surface electron accumulation layer with sheet electron density in the magnitude of ~1013 cm\u22122 on InN, either as-grown or Mg-doped, makes InN an excellent candidate for sensing application. In this paper, the response of hydrogen sensors based on Mg-doped InN films (InN:Mg) grown by molecular beam epitaxy has been investigated. The sensor exhibits a resistance variation ratio of 16.8% with response\/recovery times of less than 2 min under exposure to 2000 ppm H2\/air at 125 \u00b0C, which is 60% higher in the magnitude of response than the one based on the as-grown InN film. Hall-effect measurement shows that the InN:Mg with suitable Mg doping level exhibits larger sheet resistance, which accords with buried p-type conduction in the InN bulk. This work shows the advantage of InN:Mg and signifies its potential for sensing application.<\/jats:p>","DOI":"10.3390\/s18072065","type":"journal-article","created":{"date-parts":[[2018,6,28]],"date-time":"2018-06-28T10:53:33Z","timestamp":1530183213000},"page":"2065","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Enhanced Hydrogen Detection Based on Mg-Doped InN Epilayer"],"prefix":"10.3390","volume":"18","author":[{"given":"Shibo","family":"Wang","sequence":"first","affiliation":[{"name":"State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xinqiang","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China"},{"name":"Collaborative Innovation Center of Quantum Matter, Beijing 100871, China"},{"name":"Dongguan Institute of Opto-Electronics, Peking University, Dongguan 523808, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhaoying","family":"Chen","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ping","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qi","family":"Qi","sequence":"additional","affiliation":[{"name":"Dongguan Institute of Opto-Electronics, Peking University, Dongguan 523808, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiantong","family":"Zheng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bowen","family":"Sheng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Huapeng","family":"Liu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tao","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6743-6963","authenticated-orcid":false,"given":"Xin","family":"Rong","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mo","family":"Li","sequence":"additional","affiliation":[{"name":"Microsystem &amp; 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